In a startup, its dangerous to have favourites.
There is no upside, only downside.
Playing favourites won’t make people work harder. It can only foster resentment and politics.
Your favourite might become an instigator of the politics, and ultimately become a threat to your leadership.
Or your favourite might become a victim to the politics of jealous co-workers, and be forced out of the company.
Either way, you lose.
Don’t have a favourite beer buddy. Don’t have a favourite smoking buddy. Don’t have a favourite weekend buddy.
Don’t treat anyone differently.
Don’t play favourites.